Improvement in printing-telegraphs



THOMAS A. EDISON. Improvement in Printing-Telegraphs. No. 126,535, Patented May7,l872.

UNITED STATES PATENT EFIoE.

THOMAS A. EDISON, OF NEWARK, NElV JERSEY, ASSIGNOR TO GOLD AND STOCK TELEGRAPH COMPANY, OF NEW YORK CITY.

IMPROVEMENT IN PR Specification forming part of Letters To all whom it may concern:

Be it known that I, TEoMAs A. EnisoN, of Newark, in the county of Essex and State of New Jersey, have invented and made an Improvement in Printing-Telegraphs; and the following is declared to be a correct description of the same.

In my present invention I make use of two type-wheels, revolving with their shaft, and employ an impression-pad with aslidingshield, in which is an opening. This shield can be changed at certain points in the rotation of the type-wheel, so as to allow the impression to be made from one of the type-wheels through the opening in the shield, while the other is prevented from impressing the paper by the intervening shield. I also make use of an unison mechanism that is brought into action by two or more rotations of the type-wheels, but thrown out of action by the act of moving the pressure-lever or charging its magnet. By this means, if pulsations are sent through the line sufficient to rotate the type-wheels twice or more times Without an impression being taken, the type-wheels will be moved around untilthe stop is operative, and then the same will be stopped and the pulsations may be continued, for the purpose of bringing into unison other type-wheels,:in the same electric current, that may not be correctly set; and as soon as the circuit is reversed, or the impression or other magnet charged, all the unison devices in the circuit are simultaneously liberated; and this unison mechanism is not operative each rotation of the type-wheel; hence, as an impression is usually made each rotation, or nearly so, of the type-wheel, the unison mechanismwill not come into play except when the rotation is continued for effecting that unison.

In the drawing, Figure 1 is a vertical sectiom of my instrument. Fig. 2 is a plan of the typewheels and unison; Fig. 3 is a plan of the pad and shield; and Fig. 4 is an elevation of the device for moving said shield.

The bed a, frames b b, type-wheel magnet c, impression-magnet d, and the connections to the main line are to be of any desired character; and where the printing-magnet is made operative by reversing the polarity of the cur lNTING-TELEGRAFHS.

Patent No. 126,535, dated May 7, 1872.

be such as shown in patents heretofore granted to me. The impression-lever e, armature f, and feeding-clamps g, for the paper, may also be of any desired character. The typewheels h i are upon the shaft k, and they are moved bya step-by-step movement actuated by the armature l and lever m. n is the ratchetwheels for the pawls on the lever m,- these parts do not constitute any part of my present invention. Upon the shaft 7: is a disk, 0, revolving with such shaft, and notched at one side; and upon the impression-lever is a slide, 1", carrying the shield 8 above the pressurepad t. Upon the end of the slide 1" is a cam, 2, that can pass through the notch in the disk 0; but this can only be done when the typewheel is at a certain point; hence the shields will be held by this cam and slide, with the opening in such shield under one or other of the type wheels. A Tshaped lever, 'v, is mounted upon a pivot, 4, upon the lever e, and, by a slotted end, acts upon this slide r; and there are two pins, 5 and 6, projecting from the shaft k and contiguous to this T-lever 12, so that, if the impression-lever is moved when one pin, 5, is over said lever c, the slide and shield will be moved one way and it the typewheel is turned one space further, so as to bring the. other pin, 6, over this lever o, the movement of the slide and shield will be the other way hence the operator can bring the shield so as to print from one wheel or the other by simply rotating the type wheels around to the proper point, and then giving motion to the impression-lever. There is a screw-thread, 7, upon the shaft k, and a tooth upon the lever w takes therein; there is also a block or stop, 8, upon the type-wheel. The spring 9 draws the lever 20 away from 8 each time the tooth is lifted out of the screw7 hence, according to the number of turns of the screw- Wvhread so the type-wheels will have to be rotated before the end of the lever 20 will be brought up far enough to arrest the stop 8 and each time the lever 20 is raised, it'is drawn back to the beginning of the screw-thread; hence, if

there is a connection between 20 and the impression-lever, or the impression-magnet, the stop 8 and lever w will not come into contact when the instrument is being employed in rent, the devices for directing said current may printing; but when the pulsations are continued through the type-wheel magnet, all the type-wheels in the circuit will be stopped at the same point, as before mentioned. The lever .1 and armature 10 at the side of the core of the magnet, form a convenient means for lifting' the lever uand its tooth out of the screw 7; and this may be made to operate by a feeble pulsation, so as not to move the impression-lever.

I claim as my invention- 1. The sliding shield actuated by the T-lever 1* and pins 5 and 6, on the shaft k, in combination with the two type-wheels, substantially as set forth.

2. The revolvingdisk oand the cam 2,in com- T. A. EDISON.

Vt'itnesses:

CHAS. H. SMITH, GEo. T. PINCKNEY. 

